Delivery systems for a tooth whitener

ABSTRACT

Delivery systems for whitening teeth are provided. The delivery system includes a strip of material sized to cover a front surface of a plurality of teeth and a layer of a tooth whitening substance in contact with the strip of material. The tooth whitening substance includes a gelling agent and a whitening active selected from the group consisting of peroxides, metal chlorites, perborates, percarbonates, peroxyacids, hypochlorites, and combinations thereof. The delivery system further includes a release liner having a coating thereon, wherein the release liner exhibits less affinity for the tooth whitening substance than the tooth whitening substance exhibits for itself and for the strip of material.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of copending U.S. application Ser.No. 09/605,220, filed Jun. 28, 2000, which is a continuation of U.S.application Ser. No. 09/196,364, filed Nov. 19, 1998, now U.S. Pat. No.6,096,328, which is continuation-in-part of U.S. application Ser. No.09/042,909, filed Mar. 17, 1998, now U.S. Pat. No. 6,136,297, which is acontinuation-in-part of U.S. application Ser. No. 08/870,664, filed Jun.6, 1997, now U.S. Pat. No. 5,894,017, the substances of which areincorporated herein by reference.

BACKGROUND OF INVENTION

A recognized consumer need is a low cost commercial oral care deliverysystem that is comfortable to wear that can deliver a sufficient amountof an oral care substance for rapid delivery of an active contained insuch substance. In addition a delivery system is needed which does notrequire extensive user placement manipulation to be certain of goodcontact for optimal delivery. Furthermore, what is needed is a non-bulkyactive containment means that will permit the wearer to use the systemduring social discourse without interfering with the wearer's speech orappearance. Also needed is a containment means that will protect oralcare substance from erosion from contact with other oral surfaces and,or saliva.

SUMMARY OF INVENTION

Delivery systems for whitening teeth are provided. The delivery systemsinclude a strip of material sized to cover a front surface of aplurality of teeth and a layer of a tooth whitening substance in contactwith the strip of material. The tooth whitening substance includes agelling agent and a whitening active selected from the group consistingof peroxides, metal chlorites, perborates, percarbonates, peroxyacids,hypochlorites, and combinations thereof. The delivery systems furtherinclude a release liner having a coating thereon, wherein the releaseliner exhibits less affinity for the tooth whitening substance than thetooth whitening substance exhibits for itself and for the strip ofmaterial.

BRIEF DESCRIPTION OF DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim the present invention, it is believed that thepresent invention will be better understood from the followingdescription of preferred embodiments, taken in conjunction with theaccompanying drawings, in which like reference numerals identifyidentical elements and wherein:

FIG. 1 is a perspective view of a substantially flat strip of materialhaving rounded corners;

FIG. 2 is a perspective view of an embodiment of the present invention,disclosing the flat strip of FIG. 1 coated with an oral care substancefor treating teeth and gums;

FIG. 3 is a cross-sectional view thereof, taken along section line 3—3of FIG. 2, disclosing an example of the flat strip of material having athickness less than that of the substance coated thereon;

FIG. 4 is a cross-sectional view showing an alternative embodiment ofthe present invention, showing shallow pockets in the strip of material,which act as reservoirs for additional oral care substance coated on thestrip;

FIG. 5 is a cross-sectional plan view thereof, showing an alternativeembodiment for applying oral care substances for treating teeth toadjacent teeth having the strip of material of the present inventionconforming thereto and adhesively attached to the teeth by means of theoral care substance located between the teeth and the strip of material;

FIG. 6 is a cross-sectional elevation view of a tooth, taken alongsection line 6—6 of FIG. 5, disclosing the strip of material of thepresent invention conforming to and adhesively attached to the teeth bymeans of the oral care substance located between the teeth and the stripof material;

FIG. 7 is a cross-sectional plan view, similar to FIG. 5, showing astrip of material of the present invention conforming to the teeth andthe adjoining soft tissue and adhesively attached to both sides of theteeth by means of the oral care substance located between the teeth andthe strip of material;

FIG. 8 is a cross-sectional elevation view, taken along section line 8—8of FIG. 7, showing a strip of material of the present inventionconforming to both the tooth and the adjoining soft tissue andadhesively attached to both sides of the tooth by means of the oral caresubstance located between the tooth and the strip of material;

FIG. 9 is a perspective view of an alternative embodiment of the presentinvention, disclosing the flat strip of material coated with an oralcare substance of FIG. 2 for treating teeth and adjoining soft tissuehaving a release liner; and

FIG. 10 is a cross-sectional view of an alternative embodiment of thepresent invention, taken along section line 10—10 of FIG. 9, showing arelease liner attached to the strip of material by the oral caresubstance on the strip of material.

DETAILED DESCRIPTION

The abbreviation “cm”, as used herein, means centimeter. Theabbreviation “mm” as used herein, means millimeter.

Referring now to the drawings, and more particularly to FIGS. 1 and 2,there is shown a first preferred embodiment of the present invention,generally indicated as 10, representing a delivery system for deliveringan oral care substance to an oral surface. Delivery system 10 has astrip of material 12, which is initially substantially flat, preferablywith rounded corners.

Applied or coated onto strip of material 12 is an oral care substance14. Preferably, oral care substance 14 is homogeneous, uniformly andcontinuously coated onto strip of material 12, as shown in FIG. 3.However, oral care substance 14 may alternatively be a laminate orseparated layers of components, an amorphous mixture of components,separate stripes or spots or other patterns of different components, ora combination of these structures including a continuous coating of oralcare substance 14 along a longitudinal axis of a portion of strip ofmaterial 12.

As shown in FIG. 4, an alternative embodiment, a strip of material 12may have shallow pockets 18 formed therein. When oral care substance 14is coated on a substance-coated side of strip of material 12, additionaloral care substance 14 fills shallow pockets 18 to provide reservoirs ofadditional oral care substance 14.

FIGS. 5 and 6 show a delivery system 24 of the present invention appliedto a surface of a tooth and plurality of adjacent teeth Embedded inadjacent soft tissue 20 are a plurality of adjacent teeth 22. Adjacentsoft tissue is herein defined as soft tissue surfaces surrounding thetooth structure including: papilla, marginal gingiva, gingival sulculus,inter dental gingiva, gingival gum structure on lingual and buccalsurfaces up to and including muco-ginival junction and the pallet.

In both FIGS. 5 and 6, delivery system 24 represents strip of material12 and oral care substance 14, with oral care substance 14 on the sideof strip of material 12 facing tooth 22. Oral care substance 14 may bepre-applied to strip of material 12, or applied to strip of material 12by the delivery system user, or applied directly to the teeth 22 andthen covered by strip of material 12. In either case, strip of material12 has a thickness and flexural stiffness which enable it to conform tothe contoured surfaces of tooth 22 and to adjacent soft tissue 20. Thestrip of flexible material has sufficient flexibility to form to thecontours of the oral surface, in this figure the surface being aplurality of adjacent teeth. The strip of material is also readilyconformable to tooth surfaces and to the interstitial tooth spaceswithout permanent deformation when the delivery system is applied. Thedelivery system is applied without significant pressure.

FIGS. 7 and 8 show a delivery system 24 of the present invention appliedto both front and rear surfaces of a plurality of adjacent teeth 22 aswell as to adjacent soft tissue 20. Delivery system 24 represents stripof material 12 and oral care substance 14, with oral care substance 14on the side of strip of material 12 facing tooth 22.

FIGS. 9 and 10 shows optional release liner 27. Release liner 27 isattached to strip of material 12 by oral care substance 14. Oral caresubstance 14 is on the side of strip of material 12 facing release liner27. This side is applied to the tooth and gum surfaces once releaseliner 27 is removed.

Strip of Material

The strip of material serves as a protective barrier for the oral caresubstance. It prevents substantial leaching and/or erosion of the oralcare substance by for example, the wearer's lips, tongue, as well assaliva. This allows the active in the oral care composition to act uponthe oral surface for an extended period of time, from several minutes toseveral hours. The term “act upon” is herein defined as bringing about adesired change. For example, if the oral care substance is ananti-microbial substance, it reduces or eliminates proliferation ofmicrobial growth that has an overall positive impact on the oral cavityincluding teeth and gingival tissue.

The strip of material may comprise polymers, natural and synthetic wovenmaterials, non-woven material, foil, paper, rubber, and combinationsthereof. The strip of material may be a single layer of material or alaminate of more than one layer. Regardless of the number of layers, thestrip of material is substantially water impermeable. Preferably, thematerial is any type of polymer or combination of polymers that meet therequired flexural rigidity and are compatible with oral care substances.Suitable polymers include, but are not limited to, polyethylene,ethylvinylacetate, polyesters, ethylvinyl alcohol and combinationsthereof. Examples of polyesters include Mylar® and fluoroplastics suchas Teflon®, both manufactured by DuPont. The preferable material ispolyethylene. The strip of material is generally less than about 1 mmthick, preferably less than about 0.05 mm thick, and more preferablyfrom about 0.001 to about 0.03 mm thick. A polyethylene strip ofmaterial is preferably less than about 0.1 mm thick and more preferablyfrom about 0.005 to about 0.02 mm thick.

The shape of the strip of material is any shape and size that covers thedesired oral surface. Preferably the strip of material has roundedcorners. Rounded corners is defined as not having any sharp angles orpoints. In one example, the length of the strip of material is fromabout 2 cm to about 12 cm and preferably from about 4 cm to about 9 cm.The width of the strip of material will also depend upon the oralsurface area to be covered. In one example, the width of the strip ofmaterial is from about 0.5 cm to about 4 cm and preferably from about 1cm to about 2 cm.

The strip of material may contain shallow pockets. When the oral caresubstance is coated on a strip of material, additional oral caresubstance fills shallow pockets to provide reservoirs of additional oralcare substance. Additionally, the shallow pockets help to providetexture to the delivery system. The film will preferably have an arrayof shallow pockets. Generally, the shallow pockets are approximately 0.4mm across and 0.1 mm deep. When shallow pockets are included in thestrip of material and oral care substances are applied to it in variousthicknesses, the overall thickness of the delivery system is generallyless than about 1 mm. Preferably, the overall thickness is less thanabout 0.5 mm.

Flexural stiffness is a material property that is a function of acombination of strip thickness, width, and material modulus ofelasticity. This test is a method for measuring the rigidity ofpolyolefin film and sheeting. It determines the resistance to flexure ofa sample by using a strain gauge affixed to the end of a horizontalbeam. The opposite end of the beam presses across a strip of the sampleto force a portion of the strip into a vertical groove in a horizontalplatform upon which the sample rests. A microammeter, wired to thestrain gauge is calibrated in grams of deflection force. The rigidity ofthe sample is read directly from the microammeter and expressed as gramsper centimeter of sample strip width. In the present invention, thestrip of material has a flexural stiffness of less than about 5 grams/cmas measured on a Handle-O-Meter, model #211-300, available fromThwing-Albert Instrument Co. of Philadelphia, Pa., as per test methodASTM D2923-95. Preferably, the strip of material has a flexuralstiffness less than about 3 grams/cm, more preferably less than about 2grams/cm, and most preferably from about 0.1 grams/cm to about 1grams/cm. Preferably, the flexural stiffness of the strip of material issubstantially constant and does not change during normal use. Forexample, the strip of material does not need to be hydrated for thestrip to achieve the low flexural stiffness in the above-specifiedranges.

This relatively low stiffness enables the strip of material to cover thecontours of the oral surface with very little force being exerted. Thatis, conformity to the contours of the oral surface of the wearer's mouthis maintained because there is little residual force within the strip ofmaterial to cause it to return to its shape just prior to itsapplication to the oral surface, i.e. substantially flat. The strip ofmaterial's flexibility enables it to contact soft tissue over anextended period of time without irritation. The strip of material doesnot require pressure forming it against the oral surface.

The strip of material is held in place on the oral surface by adhesiveattachment provided by the oral care substance. The viscosity andgeneral tackiness of the oral care substance cause the strip of materialto be adhesively attached to the oral surface without substantialslippage from the frictional forces created by the lips, teeth, tongueand other oral surfaces rubbing against the strip of material whiletalking, drinking, etc. However, this adhesion to the oral surface islow enough to allow the strip of material to be easily removed by thewearer by simply peeling off the strip of material using ones finger,fingernail or rubbing with a soft implement such as a cotton balls andswabs or gauze pads. The delivery system is easily removable from theoral surfaces without the use of an instrument, a chemical solvent oragent or excessive friction. The chemical solvents include organicsolvent known for use in the oral cavity such as alcohols, and othersafe solvents such as water, that can be used to dilute the gellingagent.

The peel force required to remove the strip of material from the oralsurface is from about 1 gram to about 50 grams for a 1.5 cm strip width(approximately 17 grams/cm) is all that is required. Preferably, thepeel force is from about 10 grams to about 40 grams and more preferablyfrom about 20 grams to about 30 grams. The low peel force is desired forconsumer handling purposes. The low peel force is possible because ofthe non-aggressive nature of the oral care substance necessary to adherethe strip of material having lower flexural stiffness. That is a stripof material having high flexural stiffness higher would require anaggressive adhesive to stop the strip of material from pulling it awayfrom the contours of the oral surface it is attached to.

The strip of material may be formed by several of the film makingprocesses known in the art. Preferably, a strip of material made ofpolyethylene is made by a blown process or a cast process. Otherprocesses, including extrusion or processes that do not affect theflexural rigidity of the strip of material are also feasible .Additionally, the oral care substance may be incorporated onto the stripduring the processing of the strip. The oral care substance may be alaminate on the strip.

Oral Care Substances

The oral care substance preferably contains an active at a level whereupon directed use, promotes the benefit sought by the wearer withoutdetriment to the oral surface it is applied to. Examples of the oralconditions these actives address include, but, are not limited toappearance and structural changes to teeth, whitening, stain bleaching,stain removal, plaque removal, tartar removal, cavity prevention andtreatment, inflamed and, or bleeding gums, mucosal wounds, lesions,ulcers, aphthous ulcers, cold sores tooth abscesses, and the eliminationof mouth malodor resulting from the conditions above and other causessuch as microbial proliferation.

The amount of oral care substance applied to the strip of material ororal surface depends upon the size and capacity of the piece ofmaterial, concentration of the active, and the desired benefit sought.Generally, less than about 1 gram of oral care substance is required.Preferably, from about 0.05 grams to about 0.5 grams and more preferablyfrom about 0.1 gram to about 0.4 grams of the oral care substance isused. The amount of oral care substance per square cm of material isless than about 0.2 grams/cm², preferably from about 0.005 to about 0.1grams/cm², and more preferably from about 0.01 grams/cm² to about 0.04grams/cm².

The oral care substance of the present invention can be in the form of aviscous liquid, paste, gel, solution, or other suitable that can providesufficient adhesion. Preferably, the oral care substance is in the formof a gel. The oral care substance will have a viscosity of from about200 to about 1,000,000 cps at low shear rates (less than one 1/seconds).Preferably, the viscosity is from about 100,000 to about 800,000 cps andmore preferably from about 400,000 to about 600,000 cps.

Oral Care Actives

Suitable for oral care actives include any material that is generallyconsidered as safe for use in the oral cavity that provides changes tothe overall health of the oral cavity, and specifically the condition ofthe oral surfaces the oral care substance contacts. The level of oralcare substance in the present invention is from about 0.01% to about40%, preferably from about 0.1% to about 20%, more preferably from about0.5% to about 10%, and most preferably from about 1% to about 7%, byweight of the oral care substance.

Oral care compositions or substances of the present invention mayinclude many of the actives previously disclosed in the art. Thefollowing is a non all-inclusive list of oral care actives that may beused in the present invention.

1. Teeth Whitening Actives

Teeth whitening actives may be included in the oral care substance ofthe present invention. The actives suitable for whitening are selectedfrom the group consisting of the peroxides, metal chlorites, perborates,percarbonates, peroxyacids, and combination thereof. Suitable peroxidecompounds include hydrogen peroxide, calcium peroxide, carbamideperoxide, and mixtures thereof. Most preferred is carbamide peroxide.Suitable metal chlorites include calcium chlorite, barium chlorite,magnesium chlorite, lithium chlorite, sodium chlorite, and potassiumchlorite. Additional whitening actives may be hypochlorite and chlorinedioxide. The preferred chlorite is sodium chlorite.

2. Phosphates

Anti-tartar agents known for use in dental care products includesphosphates. Phosphates include pyrophosphates, polyphosphates,polyphosphonates and mixtures thereof. Pyrophosphates are among the bestknown for use in dental care products. Pyrophosphate ions are deliveredto the teeth derive from pyrophosphate salts. The pyrophosphate saltsuseful in the present compositions include the dialkali metalpyrophosphate salts, tetra-alkali metal pyrophosphate salts, andmixtures thereof. Disodium dihydrogen pyrophosphate (Na₂H₂P₂O₇,tetrasodium pyrophosphate (Na₄P₂O₇, and tetrapotassium pyrophosphate(K₄P₂O₇ in their unhydrated as well as hydrated forms are the preferredspecies. While any of the above mentioned pyrophosphate salts may beused, tetrasodium pyrophosphate salt is preferred.

The pyrophosphate salts are described in more detail in Kirk & Othmer,Encyclopedia of Clinical Technology Third Edition, Volume 17,Wiley-lnterscience Publishers (1982), incorporated herein by referencein its entirety, including all references incorporated into Kirk &Othmer. Additional anticalculus agents include pyrophosphates orpolyphosphates disclosed in U.S. Pat. No. 4,590,066 issued to Parran &Sakkab on May 20, 1986; polyacrylates and other polycarboxylates such asthose disclosed in U.S. Pat. No. 3,429,963 issued to Shedlovsky on Feb.25, 1969 and U.S. Pat. No. 4,304,766 issued to Chang on Dec. 8, 1981;and U.S. Pat. No. 4,661,341 issued to Benedict & Sunberg on Apr. 28,1987; polyepoxysuccinates such as those disclosed in U.S. Pat. No.4,846,650 issued to Benedict, Bush & Sunberg on Jul. 11, 1989;ethylenediaminetetraacetic acid as disclosed in British Patent No.490,384 dated Feb. 15, 1937; nitrilotriacetic acid and related compoundsas disclosed in U.S. Pat. No. 3,678,154 issued to Widder & Briner onJul. 18, 1972; polyphosphonates as disclosed in U.S. Pat. No. 3,737,533issued to Francis on Jun. 5,1973, U.S. Pat. No. 3,988,443 issued toPloger, Schmidt-Dunker & Gloxhuber on Oct. 26, 1976 and U.S. Pat. No.4,877,603 issued to Degenhardt & Kozikowski on Oct. 31, 1989; all ofthese patents are incorporated herein by reference. Anticalculusphosphates include potassium and sodium pyrophosphates; sodiumtripolyphosphate; diphosphonates, such asethane-1-hydroxy-1,1-diphosphonate, 1-azacycloheptane-1,1-diphosphonate,and linear alkyl diphosphonates; linear carboxylic acids; and sodiumzinc citrate.

Agents to may be used in place of or in combination with thepyrophosphate salt include such known materials as synthetic anionicpolymers including polyacrylates and copolymers of maleic anhydride oracid and methyl vinyl ether (e.g., Gantrez), as described, for example,in U.S. Pat. No. 4,627,977, to Gaffar et al., the disclosure of which isincorporated herein by reference in its entirety; as well as, e.g.,polyamino propoane sulfonic acid (AMPS), zinc citrate trihydrate,polyphosphates (e.g., tripolyphosphate; hexametaphosphate),diphosphonates (e.g., EHDP; AHP), polypeptides (such as polyaspartic andpolyglutamic acids), and mixtures thereof.

3. Fluoride Ion Source

Fluoride ion sources are well know for use in oral care compositions asanticaries agents. Fluoride ions are contained in a number of oral carecompositions for this purpose, particularly toothpastes. Patentsdisclosing such toothpastes include U.S. Pat. No. 3,538,230, Nov. 3,1970 to Pader et al; U.S. Pat. No. 3,689,637, Sep. 5, 1972 to Pader;U.S. Pat. No. 3,711,604, Jan. 16, 1973 to Colodney et al; U.S. Pat. No.3,911,104, Oct. 7, 1975 to Harrison; U.S. Pat. No. 3,935,306, Jan. 27,1976 to Roberts et al; and U.S. Pat. No. 4,040,858, Aug. 9, 1977 toWason.

Application of fluoride ions to dental enamel serves to protect teethagainst decay. A wide variety of fluoride ion-yielding materials can beemployed as sources of soluble fluoride in the instant compositions.Examples of suitable fluoride ion-yielding materials are found in Brineret al; U.S. Pat. No. 3,535,421; issued Oct. 20, 1970 and Widder et al;U.S. Pat. No. 3,678,154; issued Jul. 18, 1972, both patents beingincorporated herein by reference. Preferred fluoride ion sources for useherein include sodium fluoride, potassium fluoride and ammoniumfluoride. Sodium fluoride is particularly preferred. Preferably theinstant compositions provide from about 50 ppm to 10,000 ppm, morepreferably from about 100 to 3000 ppm, of fluoride ions in the aqueoussolutions that contact dental surfaces when used with the strip ofmaterial used in the mouth.

4. Antimicrobial Agents

Antimicrobial agents can also be present in the oral care compositionsor substances of the present invention. Such agents may include, but arenot limited to, 5-chloro-2-(2,4-dichlorophenoxy)-phenol, commonlyreferred to as triclosan, and described in The Merck Index, 11th ed.(1989), pp. 1529 (entry no. 9573) in U.S. Pat. No. 3,506,720, and inEuropean Patent Application No. 0,251,591 of Beecham Group, PLC,published Jan. 7, 1988; phthalic acid and its salts including, but notlimited to those disclosed in U.S. Pat. No. 4,994,262, Feb. 19, 1991,substituted monoperthalic acid and its salts and esters as disclosed inU.S. Pat. Nos. 4,990,329, Feb. 5, 1991, 5,110,583, May 5, 1992 and4,716,035, Dec. 29, 1987, all to Sampathkumar; preferably magnesiummonoperoxy phthalate, chlorhexidine (Merck Index, no. 2090), alexidine(Merck Index, no. 222; hexetidine (Merck Index, no. 4624); sanguinarine(Merck Index, no. 8320); benzalkonium chloride (Merck Index, no. 1066);salicylanilide (Merck Index, no. 8299); domiphen bromide (Merck Index,no. 3411); cetylpyridinium chloride (CPC) (Merck Index, no. 2024;tetradecylpyridinium chloride (TPC); N-tetradecyl-4-ethylpyridiniumchloride (TDEPC); octenidine; delmopinol, octapinol, and otherpiperidino derivatives; nicin preparations; zinc/stannous ion agents;antibiotics such as augmentin, amoxicillin, tetracycline, doxycycline,minocycline, and metronidazole; and analogs and salts of the above;essential oils including thymol, geraniol, carvacrol, citral,hinokitiol, eucalyptol, catechol (particularly 4-allyl catechol) andmixtures thereof; methyl salicylate; hydrogen peroxide; metal salts ofchlorite and mixtures of all of the above.

5. Anti-inflammatory Agents

Anti-inflammatory agents can also be present in the oral carecompositions or substances of the present invention. Such agents mayinclude, but are not limited to, non-steroidal anti-inflammatory agentsor NSAIDs such as ketorolac, flurbiprofen, ibuprofen, naproxen,indomethacin, aspirin, ketoprofen, piroxicam and meclofenamic acid. Useof NSAIDs such as Ketorolac are claimed in U.S. Pat. No. 5,626,838,issued May 6, 1997, herein incorporated by reference. Disclosed thereinare methods of preventing and, or treating primary and reoccurringsquamous cell carcinoma of the oral cavity or oropharynx by topicaladministration to the oral cavity or oropharynx an effective amount ofan NSAID.

6. Nutrients

Nutrients may improve the condition of the oral cavity and can beincluded in the oral care compositions or substances of the presentinvention. Nutrients include minerals, vitamins, oral nutritionalsupplements, enteral nutritional supplements, and mixtures thereof.

Minerals that can be included with the compositions of the presentinvention include calcium, phosphorus, fluoride, zinc, manganese,potassium and mixtures thereof. These minerals are disclosed in DrugFacts and Comparisons (loose leaf drug information service), WoltersKluer Company, St. Louis, Mo., 1997, pp 10-17; incorporated herein byreference.

Vitamins can be included with minerals or used separately. Vitaminsinclude Vitamins C and D, thiamine, riboflavin, calcium pantothenate,niacin, folic acid, nicotinamide, pyridoxine, cyanocobalamin,para-aminobenzoic acid, bioflavonoids, and mixtures thereof. Suchvitamins are disclosed in Drug Facts and Comparisons (loose leaf druginformation service), Wolters Kluer Company, St. Louis, Mo., 1997, pp.3-10; incorporated herein by reference.

Oral nutritional supplements include amino acids, lipotropics, fish oil,and mixtures thereof, as disclosed in Drug Facts and Comparisons (looseleaf drug information service), Wolters Kluer Company, St. Louis, Mo.,1997, pp. 54-54e; incorporated herein by reference. Amino acids include,but, are not limited to L-Tryptophan, L-Lysine, Methionine, Threonine,Levocarnitine or L-carnitine and mixtures thereof. Lipotropics include,but, are not limited to choline, inositol, betaine, linoleic acid,linolenic acid, and mixtures thereof. Fish oil contains large amounts ofOmega-3 (N-3) Polyunsaturated fatty acids, eicosapentaenoic acid anddocosahexaenoic acid.

Entenal nutritional supplements include, but, are not limited to proteinproducts, glucose polymers, corn oil, safflower oil, medium chaintriglycerides as disclosed in Drug Facts and Comparisons (loose leafdrug information service), Wolters Kluer Company, St. Louis, Mo., 1997,pp. 55-57; incorporated herein by reference.

7. Enzymes

An individual or combination of several compatible enzymes can beincluded in the oral care composition or substance of the presentinvention. Enzymes are biological catalysts of chemical reactions inliving systems. Enzymes combine with the substrates on which they actforming an intermediate enzyme-substrate complex. This complex is thenconverted to a reaction product and a liberated enzyme which continuesits specific enzymatic function.

Enzymes provide several benefits when used for cleansing of the oralcavity. Proteases break down salivary proteins which are absorbed ontothe tooth surface and form the pellicle; the first layer of resultingplaque. Proteases along with lipases destroy bacteria by lysing proteinsand lipids which form the structural component of bacterial cell wallsand membranes. Dextranases break down the organic skeletal structureproduced by bacteria that forms a matrix for bacterial adhesion.Proteases and amylases, not only present plaque formation, but alsoprevent the development of calculus by breaking-up thecarbohydrate-protein complex that binds calcium, preventingmineralization.

Enzymes useful in the present invention include any of the commerciallyavailable proteases, glucanohydrolases, endoglycosidases, amylases,mutanases, lipases and mucinases or compatible mixtures thereof.Preferred are the proteases, dextranases, endoglycosidases andmutanases, most preferred being papain, endoglycosidase or a mixture ofdextranase and mutanase. Additional enzymes suitable for use in thepresent invention are disclosed in U.S. Pat. No. 5,000,939 to Dring etal., Mar. 19, 1991; U.S. Pat. No. 4,992,420 to Neeser, Feb. 12, 1991;U.S. Pat No. 4,355,022 to Rabussay, Oct. 19, 1982; U.S. Pat. No.4,154,815 to Pader, May 15, 1979; U.S. Pat. No. 4,058,595 to Colodney,Nov. 15, 1977; U.S. Pat. No. 3,991,177 to Virda et al., Nov. 9, 1976 andU.S. Pat. No. 3,696,191 to Weeks, Oct. 3, 1972; all incorporated hereinby reference.

8. Mouth and Throat Products

Other materials that can be used with the present invention includecommonly known mouth and throat products. Such products are disclosed inDrug Facts and Comparisons (loose leaf drug information service),Wolters Kluer Company, St. Louis, Mo., 1997, pp. 520b-527; incorporatedherein by reference. These products include, but, are not limited toanti-fungal, antibiotic and analgesic agents.

9. Antioxidants

Antioxidants are generally recognized as useful in compositions such asthose of the present invention. Antioxidants are disclosed in texts suchas Cadenas and Packer, The Handbook of Antioxidants©, 1996 by MarcelDekker, Inc., incorporated herein by reference. Antioxidants that may beincluded in the oral care composition or substance of the presentinvention include, but are not limited to Vitamin E, ascorbic acid, Uricacid, carotenoids, Vitamin A, flavonoids and polyphenols, herbalantioxidants, melatonin, aminoindoles, lipoic acids and mixturesthereof.

10. H-2 Antagonists

Histamine-2 (H-2 or H₂) receptor antagonist compounds (H-2 antagonists)may be used in the oral care composition of the present invention. Asused herein, selective H-2 antagonists are compounds that block H-2receptors, but do not have meaningful activity in blocking histamine-1(H-1 or H₁) receptors. Selective H-2 antagonists stimulates thecontraction of smooth muscle from various organs, such as the gut andbronchi; this effect can be suppressed by low concentrations ofmepyramine—a typical antihistaminic drug. The pharmacological receptorsinvolved in these mepyramine-sensitive histamine responses have beendefined as H-1 receptors (Ash, A. S. F. & H. O. Schild, Brit. J.Pharmacol Chemother., Vol. 27 (1966), p. 427, incorporated herein byreference). Histamine also stimulates the secretion of acid by thestomach (Loew, E. R. & O. Chickering, Proc. Soc. Exp. Biol. Med., Vol.48 (1941), p. 65, incorporated herein by reference), increases the heartrate (Trendelenburg, U., J. Pharmacol., Vol. 130 (1960), p. 450,incorporated herein by reference), and inhibits contractions in the ratuterus (Dews, P. B. & J. D. P. Graham, Brit. J. Pharmacol. Chemother.,Vol. 1 (1946), p. 278, incorporated herein by reference); these actionscannot be antagonized by mepyramine and related drugs. The H-2antagonists useful in the oral care compositions or substances are thosethat blockade the receptors involved in mepyramine-insensitive, non-H-1(H-2), histamine responses, and do not blockade the receptors involvedin mepyramine-sensitive histamine responses.

Selective H-2 antagonists are those compounds found to be H-2antagonists through their performance in classical preclinical screeningtests for H-2 antagonist function. Selective H-2 antagonists areidentified as compounds which can be demonstrated to function ascompetitive or non-competitive inhibitors of histamine-mediated effectsin those screening models specifically dependent upon H-2 receptorfunction, but to lack significant histamine antagonist activity in thosescreening models dependent upon H-1 receptor function. Specifically,this includes compounds that would be classified as described by Black,J. W., W. A. M. Duncan, C. J. Durant, C. R. Ganellin & E. M. Parsons,“Definition and Antagonism of Histamine H₂-Receptors”, Nature, Vol. 236(Apr. 21, 1972), pp. 385-390 (Black), incorporated herein by reference,as H-2 antagonists if assessed as described by Black through testingwith the guinea pig spontaneously beating right atria in vitro assay andthe rat gastric acid secretion in vivo assay, but shown to lack insignificant H-1 antagonist activity relative to H-2 antagonist activity,if assessed as described by Black with either the guinea pig ileumcontraction in vitro assay or the rat stomach muscle contraction in vivoassay. Preferably selective H-2 antagonists demonstrate no significantH-1 activity at reasonable dosage levels in the above H-1 assays.Typical reasonable dosage level is the lowest dosage level at which 90%inhibition of histamine, preferably 99% inhibition of histamine, isachieved in the above H-2 assays.

Selective H-2 antagonists include compounds meeting the above criteriawhich are disclosed in U.S. Pat. Nos. 5,294,433 and 5,364,616 Singer etal., issued Mar. 15, 1994 and Nov. 15, 1994 respectively and assigned toProcter & Gamble; both herein incorporated by reference. wherein theselective H-2 antagonist is selected from the group consisting ofcimetidine, etintidine, ranitidine, ICIA-5165, tiotidine, ORF-17578,lupitidine, donetidine, famotidine, roxatidine, pifatidine, lamtidine,BL-6548, BMY-25271, zaltidine, nizatidine, mifentidine, BMY-52368,SKF-94482, BL-6341A, ICI-162846, ramixotidine, Wy-45727, SR-58042,BMY-25405, loxtidine, DA-4634, bisfentidine, sufotidine, ebrotidine,HE-30-256, D-16637, FRG-8813, FRG-8701, impromidine, L-643728, andHB-408.4. Particularly preferred is cimetidine (SKF-92334),N-cyano-N′-methyl-N″-(2-(((5-methyl-1H-imidazol-4-yl)methyl)thio)ethyl)guanidine:

Cimetidine is also disclosed in the Merck Index, 11th edition (1989), p.354 (entry no. 2279), and Physicians' Desk Reference, 46th edition(1992), p. 2228. Related preferred H-2 antagonists include burimamideand metiamide.

As previously mentioned, the oral care substance of the presentinvention can be in a variety forms, but, most preferable is a gel,particularly an aqueous gel. The gel is a high viscosity matrix formedfrom gelling agents known in the art. These gelling agents are safe fororal use, do not readily dissolve in saliva, and do not react with orinactivate the oral care compounds incorporated into them. Generally,the gelling agent is a swellable polymer. Furthermore, the gel formedwith these agents provide sufficient adhesive attachment of the filmmaterial to the targeted area of the mouth. The level of gelling agentto form the gel composition is from about 0.1% to about 15%, preferablyfrom about 1% to about 10%, more preferably from about 2% to about 8%,and most preferably from about 4% to about 6%, by weight of the oralcare composition or substance.

Suitable gelling agents useful in the present invention includecarboxypolymethylene, carboxymethyl cellulose, carboxypropyl cellulose,polyoxamers, carrageenan, Veegum, carboxyvinyl polymers, and naturalgums such as gum karaya, xanthan gum, Guar gum, gum arabic, gumtragacanth, and mixtures thereof. The preferable gelling agent for usein the present invention is carboxypolymethylene, obtained from B. F.Goodrich Company under the tradename Carbopol®. Particularly preferableCarbopols include Carbopol 934, 940, 941, 956 and mixtures thereof.Particularly preferred is Carbopol 956. Carboxypolymethylene is aslightly acidic vinyl polymer with active carboxyl groups. The normalconcentration of various carboxypolymethylene resins in water, accordingto the manufacturer, is below about 2%. However, it has been found thatby preparing supersaturated carboxypolymethylene compositions having anabsolute concentration in the ranges specified above, suitable highviscosity oral gel compositions may be prepared.

The concentrated carboxypolymethylene gels have a number of importantcharacteristics in addition to high viscosity. Enoughcarboxypolymethylene is added to the oral gel compositions beyond thatrequired to provide high viscosity such that a significant quantity ofsaliva or water is required to lower the viscosity to the point that thecomposition may be diluted and washed out by saliva. The concentratedcarboxypolymethylene composition also has a unique tackiness orstickiness which retains and seals the strip material against thetargeted oral cavity surface it is affixed to, particularly teeth.However, care should be taken to avoid too much carboxypolymethylenethereby making insertion or withdrawal of the strip material difficult.

If the oral care substance is an aqueous gel, the water present in thegel compositions should preferably be deionized and free of organicimpurities. Water comprises from about 0.1% to 95%, preferably fromabout 5% to about 90%, and most preferably from about 10% to about 80%,by weight of the oral care substance. This amount of water includes thefree water that is added plus that amount that is introduced with othermaterials.

A pH adjusting agent may also be added to optimize the storage stabilityof the gel and to make the substance safe for oral tissue. These pHadjusting agents, or buffers, can be any material which is suitable toadjust the pH of the oral care substance. Suitable materials includesodium bicarbonate, sodium phosphate, sodium hydroxide, ammoniumhydroxide, sodium stannate, triethanolamine, citric acid, hydrochloricacid, sodium citrate, and combinations thereof. The pH adjusting agentsare added in sufficient amounts so as to adjust the pH of the gelcomposition to about 4.5 to about 11, preferably from about 5.5 to about8.5, and more preferably from about 6 to about 7. pH adjusting agentsare generally present in an amount of from about 0.01% to about 15% andpreferably from about 0.05% to about 5%, by weight of the oral caresubstance.

While the gel described above provides sufficient adhesiveness,additional gelling agents may also be included in the formula to helpthe active ingredients adhere to the tissues of the oral cavity.Suitable agents include both polymers with limited water solubility aswell as polymers lacking water solubility. These polymers deposit a thinfilm on both the oral cavity's soft and hard tissues when salivacombines with the instant composition. Suitable limited water solubilityadhesives include: hydroxy ethyl or propyl cellulose. Adhesives lackingwater solubility include: ethyl cellulose and polyox resins. Anotherpossible adhesive suitable for use in the instant composition ispolyvinylpyrrolidone with a molecular weight of about 50,000 to about300,000. Still another possible adhesive suitable for use in the instantcomposition is a combination of Gantrez and the semisynthetic,water-soluble polymer carboxymethyl cellulose.

An additional carrier material may also be added to the oral caresubstance. Carrier materials can be humectants. Suitable humectantsinclude glycerin, sorbitol, polyethylene glycol, propylene glycol, andother edible polyhydric alcohols. Humectants are generally present in anamount of from about 10% to about 95% and preferably from about 50% toabout 80%, by weight of the oral care substance or composition. Inaddition to the above materials of the gel of the present invention, anumber of other components can also be added to the oral care substance.Additional components include, but are not limited to, flavoring agents,sweetening agents, xylitol, opacifiers, coloring agents, and chelantssuch as ethylenediaminetetraacetic acid. These additional ingredientscan also be used in place of the compounds disclosed above.

The Release Liner

The release liner may be formed from any material which exhibits lessaffinity for the oral care substance than the oral care substanceexhibits for itself and for the strip of material. The release linerpreferably comprises a rigid sheet of material such as polyethylene,paper, polyester, or other material which is then coated with anon-stick type material. The release liner material may be coated withwax, silicone, teflon, fluoropolymers, or other non-stick typematerials. A preferred release liner is Scotchpak® produced by 3M. Therelease liner may be cut to substantially the same size and shape as thestrip of material or the release liner may be cut larger than the stripof material to provide a readily accessible means for separating thematerial from the strip. The release liner may be formed from a brittlematerial which cracks when the strip is flexed or from multiple piecesof material or a scored piece of material. Alternative, the releaseliner may be in two overlapping pieces such as a typical adhesive stripbandage design. A further description of materials suitable as releaseagents is found in Kirk-Othmer Encyclopedia of Chemical Technology,Fourth Edition, Volume 21, pp. 207-218, incorporated herein byreference.

EXAMPLES

The strip of material 12 is preferably a 0.013 thick piece ofpolyethylene film. The film preferably has an array of shallow pockets,typically 0.4 mm across and 0.1 mm deep. The strip of material 12 has aflexural stiffness of about 0.6 grams/centimeter as measured on aHandle-O-Meter, model #211-300, available from Thwing-Albert InstrumentCo. of Philadelphia, Pa., as per test method ASTM D2923-95.

An example of a tooth whitener is a gel described as follows: combine70% glycerin, 5% carboxypolymethylene, 10% carbamide peroxide, and 15%water adjusted to pH 6.5 with sodium hydroxide. Mix until homogeneous.Commercial tooth whiteners, such as Opalescence and Nu-Pro Gold are alsooperable with the delivery system of the present invention.

An example of an oral gel composition of the subject inventioncontaining H-2 antagonists, made by routine processing methods,comprises mixing 2.50% hydroxyethyl cellulose, 0.09% sodium fluoride,0.05% sodium saccharin, 1.00% ranitidine, and purified water q.s.

An example of an oral gel composition of the subject inventioncontaining enzymes, made by routine processing methods, comprises61.814% sorbitol, 0.314% Carbopol 956, 0.534% xantham gum, 1.132% citricacid, 6.291 sodium citrate, 5.033% sodium lauroyl sarcosinate (30%solution), 7.864% endoglycosidase (3.2% solution), 0.305% sodiumfluoride, water q.s.

An example of an oral gel composition of the subject inventioncontaining antimicrobial actives, made by routine processing methods,comprises from 21.2% to 21.5% glycerin, 6.0% Carbopol 956, 40.0%propylene glycol, 2.5% sodium hydroxide (50% solution), from 0.1% to0.3% Triclosan and water q.s.

Method of Use

In practicing the present invention, a strip of material is applied tothe desired oral surface by the wearer. The side of the material facingthe oral surface is coated with a oral care substance that is preferablyin a highly viscous state. This oral care substance provides a vehiclefor the active as well as tackiness between the oral surfaces and thestrip of material, holding the strip of material in place for extendedperiods of time. For oral care actives other than teeth whiteners, theperiod over which the strip of material is used is from about 1 minuteto about 8 hours for actives that require long term diffusion into theoral surface, preferably from about 1 to about 120 minutes and mostpreferably from about 30 to about 60 minutes.

There are many methods using the present invention to reduce oreliminate the proliferation of microbial and bacterial growth in theoral cavity. Such growth is known to be responsible for development oforal conditions including, but not limited to mouth and breath odor,plaque accumulation, gingival inflammation and bleeding of the gumtissue. Prolonged attachment by certain oral bacteria has also beenimplicated in more progressive periodontal diseases. Numerous articlesexist in the literature that describe the advantages of controllingbacterial growth in regard to maintaining good oral well-being of theindividual.

Among these methods is one that comprises the steps of first applying agel comprising an antimicrobial agent, preferably in a highly viscousstate, to the strip of material of the present invention. The strip ofmaterial with the applied gel is applied to the oral surface, preferablythe front surface of a plurality of adjacent teeth and their surroundinggum tissue, with adhesive attachment between the strip of material andthe oral surface. This provides sufficient attachment for holding thedelivery system in place for a sufficient time to allow theantimicrobial agent to act upon the oral surface. The conformable stripis removed after a period of time for the antimicrobial agent to beeffective. Such a period includes from just prior to retiring or uponawakening. Whenever the strip is removed the excess gel residueremaining on the applied surface may be removed by means such asbrushing and, or rinsing. Such a method has been found particularlyuseful in the eliminating mouth odors generated while sleeping.

The strip of material readily conforms to the oral care surface bylightly pressing it there against. The strip of material is easilyremoved by the wearer by peeling it off using a finger or fingernail.Preferably each successive treatment uses a fresh strip of material.

In the situation were the oral care surface is the surface of teeth, isnot unnecessary to prepare the teeth surface before applying thedelivery system of the present invention. For example, the wearer may ormay not choose to brush his teeth or rinse his mouth before applying thedelivery system. The surfaces of the teeth are not required to be driedor to be excessively wet with saliva or water before the strip ofmaterial is applied.

Preferably, the strip of material and substances almost unnoticeablewhen worn, preferably transparent. Thinness of the strip of material mayalso provide higher temperature of the oral surface wherein the warmertemperature accelerates the rate of diffusion of the active materialinto the oral surface.

When the wearer removes the strip of material from the tooth, there maybe a residual amount of oral care substance remaining on the surface.The amount residual oral care substance, however, will not be greatsince it has affinity for both the film and for itself. Any residualoral care substance may be easily removed by wiping, brushing or rinsingthe oral surface.

While particular embodiments of the present invention have beenillustrated and described, it will be obvious to those skilled in theart that various changes and modifications may be made without departingfrom the spirit and scope of the invention, and it is intended to coverin the appended claims all such modifications that are within the scopeof the invention.

What is claimed is:
 1. A delivery system for whitening teeth,comprising: a strip of material sized to cover a front surface of aplurality of teeth; a layer of a tooth whitening substance in contactwith said strip of material, said tooth whitening substance comprising agelling agent and a whitening active selected from the group consistingof peroxides, metal chlorites, perborates, percarbonates, peroxyacids,hypochlorites, and combinations thereof; and a release liner having acoating thereon, wherein said release liner exhibits less affinity forsaid tooth whitening substance than said tooth whitening substanceexhibits for itself and for said strip of material.
 2. The deliverysystem of claim 1, wherein said release liner is formed from a rigidsheet of material.
 3. The delivery system of claim 1, wherein saidgelling agent is selected from the group consisting ofcarboxypolymethylene, carboxymethyl cellulose, carboxypropyl cellulose,polyoxamers, carrageenan, Veegum, carboxyvinyl polymers, and naturalgums.
 4. The delivery system of claim 3, wherein said gelling agent iscarboxypolymethylene.
 5. The delivery system of claim 4, wherein thelevel of said gelling agent is between about 0.1% and about 15% byweight of said tooth whitening substance.
 6. The delivery system ofclaim 5, wherein the level of said gelling agent is between about 2% andabout 8% by weight of said tooth whitening composition.
 7. The deliverysystem of claim 4, wherein said tooth whitening substance furtherincludes water.
 8. The delivery system of claim 7, wherein said toothwhitening substance comprises between about 10% and about 80% water byweight of said tooth whitening substance.
 9. The delivery system ofclaim 7, wherein said whitening active is a peroxide.
 10. The deliverysystem of claim 9, wherein said strip of material is formed frompolyethylene.
 11. A delivery system for whitening teeth, comprising: aflexible strip of material sized to cover a front surface of a pluralityof teeth, wherein said strip of material is substantially flat; a thinlayer of a tooth whitening substance in contact with said flexible stripof material, said tooth whitening substance comprising a gelling agentand a whitening active selected from the group consisting of peroxides,metal chlorites, perborates, percarbonates, peroxyacids, hypochlorites,and combinations thereof, wherein the level of said gelling agent isbetween about 0.1% and about 15% by weight of said tooth whiteningcomposition; and a release liner having a coating thereon, wherein saidrelease liner exhibits less affinity for said tooth whitening substancethan said tooth whitening substance exhibits for itself and for saidflexible strip of material.
 12. The delivery system of claim 11, whereinsaid release liner is formed from a rigid sheet of material.
 13. Thedelivery system of claim 11, wherein said gelling agent is selected fromthe group consisting of carboxypolymethylene, carboxymethyl cellulose,carboxypropyl cellulose, polyoxamers, carrageenan, Veegum, carboxyvinylpolymers, and natural gums.
 14. The delivery system of claim 13, whereinsaid gelling agent is carboxypolymethylene.
 15. The delivery system ofclaim 14, wherein the level of said gelling agent is between about 2%and about 8% by weight of said tooth whitening composition.
 16. Thedelivery system of claim 13, wherein said tooth whitening substancefurther includes water.
 17. The delivery system of claim 16, whereinsaid tooth whitening substance comprises between about 10% and about 80%water by weight of said tooth whitening substance.
 18. The deliverysystem of claim 16, wherein said whitening active is a peroxide.
 19. Thedelivery system of claim 18, wherein said flexible strip of material isformed from polyethylene.
 20. The delivery system of claim 1, whereinsaid strip of material is further sized to cover soft tissue adjacentsaid plurality of teeth.
 21. The delivery system of claim 20, whereinthe adjacent soft tissue is the marginal gingiva.
 22. The deliverysystem of claim 1, wherein said strip of material is further sized tocover a rear surface of the plurality of teeth.
 23. The delivery systemof claim 1, wherein said layer of said tooth whitening substance iscontinuously coated on said strip of material.